Upstream sweep test with sweep server signaling

1. A test instrument connectable to a network to perform a sweep test in the network, the test instrument comprising: a port connectable to a test point in the network; a processing circuit to: insert, via the port, test signals into an upstream path of the network at the test point, wherein the test point is located in the network, downstream from a remote physical (R-PHY) device connected to a cable modem termination system (CMTS) core, wherein the R-PHY device comprises at least one of a downstream quadrature amplitude modulation (QAM) and orthogonal frequency-division multiplexing (OFDM) modulator, an upstream QAM and OFDM demodulator, and pseudowire logic to connect to Converged Cable Access Platform (CCAP) core; receive frequency response data of the test signals measured by the R-PHY device from a sweep server via a telemetry channel, wherein the sweep server communicates with the CMTS core to obtain the measured frequency response data for transmission to the test instrument, wherein the telemetry channel is used to transmit or receive signals over another network; and determine a frequency response for the network between the test point and the R-PHY device based on the frequency response data, wherein the sweep test comprises performing measurements over a range of frequencies and wherein the frequency response for the network between the test point and the R-PHY device comprises information for a path in the network, the frequency response comprising Fast Fourier Transform (FFT) data.

2. The test instrument of claim 1 , wherein to initiate the sweep test to receive the frequency response data, the processing circuit is to: transmit a sweep request message to the sweep server; receive an upstream channel plan from the sweep server in response to the sweep request message; and insert the test signals into frequencies in the upstream path that are specified in the upstream channel plan.

3. The test instrument of claim 1 , wherein the processing circuit is to transmit a message, including a network address of the test instrument that is to be included in the test signals, to the sweep server, and the sweep server sends the network address of the test instrument to the CMTS core for determining the frequency response data.

4. The test instrument of claim 3 , wherein the CMTS core instructs the R-PHY device to send the frequency response data for the test signals having the network address of the test instrument to the CMTS core, and the CMTS core transmits the frequency response data to the sweep server.

5. The test instrument of claim 1 , wherein the test instrument exchanges messages with the sweep server via a telemetry channel to receive the frequency response data.

6. The test instrument of claim 5 , wherein the telemetry channel comprises an out of band channel.

7. The test instrument of claim 6 , wherein the out of band telemetry channel is in a second network, and the test instrument comprises an interface connectable to the second network or connectable to a device to access the second network.

8. The test instrument of claim 6 , wherein the out of band telemetry channel comprises an R-PHY narrowband digital forward channel and a narrowband digital return channel.

9. The test instrument of claim 6 , wherein the out of band telemetry channel comprises a channel in a cellular network.

10. The test instrument of claim 5 , wherein the telemetry channel comprises an in band channel carrying network traffic for customer premises connected to the network.

11. The test instrument of claim 1 , wherein the frequency response data comprises at least one of an amplitude-versus-frequency response of the test signals transmitted from the test instrument, and a difference in power between the test signals transmitted from the test instrument and the test signals received at the R-PHY device for a set of frequencies in the upstream path.

12. A test instrument to test channels in a cable television network comprising a cable modem termination system (CMTS) having a distributed architecture, the test instrument comprising: at least one port connectable to the cable television network; a transmission circuit coupled to the at least one port to transmit test signals in the cable television network; and a processing circuit to facilitate a sweep test in the cable television network between the test instrument and the CMTS, wherein the CMTS comprises a CMTS core and an R-PHY device, wherein the R-PHY device comprises at least one of a downstream quadrature amplitude modulation (QAM) and orthogonal frequency-division multiplexing (OFDM) modulator, an upstream QAM and OFDM demodulator, and pseudowire logic to connect to Converged Cable Access Platform (CCAP) core, the processing circuit to: transmit a sweep request message to a sweep server connected to the CMTS to request the sweep test with the CMTS; generate test packets for conducting the sweep test in response to receiving a request granted message from the sweep server, wherein the test packets are transmitted in test signals by the transmission circuit in an upstream path of the cable television network to the CMTS; receive, from the sweep server via a telemetry channel, frequency response data of the test signals measured by the R-PHY device, wherein the sweep server communicates with the CMTS to obtain the frequency response data for transmission to the test instrument, wherein the telemetry channel is used to transmit or receive signals over another network; and determine a frequency response for the upstream path based on the frequency response data, wherein the sweep test comprises performing measurements over a range of frequencies and wherein the frequency response for the network between the test point and the R-PHY device comprises information for a path in the network, the frequency response comprising Fast Fourier Transform (FFT) data.

13. The test instrument of claim 12 , wherein the request granted message from the sweep server includes an upstream channel plan, and the test signals are transmitted on frequencies in the upstream path that are specified in the upstream channel plan.

14. The test instrument of claim 12 , wherein the sweep request message includes a network address of the test instrument that is to be included in the test signals, and the sweep server sends the network address of the test instrument to the CMTS for determining the frequency response data of the test signals.

15. The test instrument of claim 14 , wherein the CMTS core instructs the R-PHY device to send the frequency response data for the test signals having the network address of the test instrument to the CMTS core, and the CMTS core transmits the frequency response data to the sweep server.

16. The test instrument of claim 12 , wherein the sweep request message, the request granted message, and the frequency response data are provided between the test instrument and the sweep server via a telemetry channel.

17. The test instrument of claim 16 , wherein the telemetry channel comprises an out of band channel.

18. The test instrument of claim 17 , wherein the out of band telemetry channel is in a second network, and the test instrument comprises an interface connectable to the second network or connectable to a device to access the second network.

19. The test instrument of claim 17 , wherein the out of band telemetry channel comprises an R-PHY narrowband digital forward channel and a narrowband digital return channel.

20. A method executable by a test instrument to perform a sweep test in a cable television network, the method comprising: transmitting a sweep request message to a sweep server connected to a cable modem termination system (CMTS) to request the sweep test with the CMTS, wherein the CMTS comprises a CMTS core and an R-PHY device, wherein the R-PHY device comprises at least one of a downstream QAM and OFDM modulator, an upstream quadrature amplitude modulation (QAM) and orthogonal frequency-division multiplexing (OFDM) demodulator, and pseudowire logic to connect to Converged Cable Access Platform (CCAP) core; receiving a request granted message from the sweep server in response to the sweep request message, wherein the request granted message specifies upstream channels in the cable television network for conducting the sweep test; transmitting test signals in the upstream channels towards the R-PHY device; receiving, from the sweep server via a telemetry channel, frequency response data of the test signals measured by the R-PHY device, wherein the sweep server communicates with the CMTS core to obtain the measured frequency response data for transmission to the test instrument, wherein the telemetry channel is used to transmit or receive signals over another network; and determining a frequency response for the upstream channels based on the frequency response data, wherein the sweep test comprises performing measurements over a range of frequencies and wherein the frequency response for the network between the test point and the R-PHY device comprises information for a path in the network, the frequency response comprising Fast Fourier Transform (FFT) data.